Integral weatherproof plastic lid



BY 3, 24 2? WW P. H. WINTER INTEGRAL WEATHERPROOF PLASTIC LID AND HINGE FOR ELECTRICAL OUTLETS Flled July 26, 1962 4 --II 6 w v/ v%///V///// 1, w 3 fr, ll .h I I m 4 M v United States Patent York Filed July 26, 1962, Ser. No. 212,660 Claims. (Cl. 220-35) This invention relates to a weatherproof cover or lid for an electrical outlet and more particularly to such cover having an integral hinge reducing the construction to extreme simplicity.

It is a general object of the present invention to provide a novel and improved weatherproof lid and integral hinge construction for use with electrical outlets of the type having a wall plate through which the outlet face is exposed.

More particularly it is an object of the invention to provide a novel one-piece construction of lid, hinge and gasket for assembly with the customary wall plate through which an electrical outlet is exposed whereby the latter, when not in use, is covered and protected from the weather.

An important object of the invention resides in the double hinge arrangement which provides space for the closing springs and houses and shields them.

Another important object of the invention resides in the provision of an integral flexible sealing lip on the inner face of the lid for water-tight engagement with the wall plate beyond the opening therein for the outlet.

Other and further objects and specific features of the invention will be more apparent to those skilled in the art upon a careful consideration of the following specification and the accompanying drawing, whereinis disclosed a single exemplary embodiment of the invention with the understanding that such changes and modifications may be made therein as fall within the scope of the appended claims without departing from the spirit of the invention.

In said drawing:

FIGURE 1 is a perspective View of the lid and hinge unit shown mounted on a conventional wall plate;

FIGURE 2 is a face view thereof on a larger scale;

FIGURE 3 is a vertical section through the assembly of FIGURE 2 taken on broken line 33 thereof; and

FIGURE 4 is a fragmentary section on the same line, but on an enlarged scale, of the hinge portion of the lid as moulded and before bending on the hinge lines.

The problem of providing a satisfactory and yet low cost weatherproof hinged cover for convenience outlets exposed through wall plates for use outdoors or in damp areas has heretofore been attacked by manufacturers by the use of a metal cover or lid hinged in more or less conventional fashion to the wall plate which must thus be made especially for the purpose to provide extending posts or ears to hold the hinge pintle and to provide proper accommodations for the closing spring, without which such devices do not function properly since the necessary gaskets seal well only under considerable pressure. These gasket items present a further difliculty in the metal lid with the fixed hinge pins since they must be secured to the undersurface of the lid by either fastenings, interlocking components or the use of an adhesive, which latter has usually turned out to be unsatisfactory, for over a period of time the gasket seems to separate from the cover.

Even more costly constructions have been resorted to by many manufacturers of high grade devices, by forming an annular spigot on the wall plate, surrounding the face of the outlet, threading this externally and providing an internally threaded cap and inset gasket, but since this is a removable item it then must be attached by a chain or the like to prevent it from becoming lost and the whole ICC operation becomes an expensive one to manufacture and one which is slow to use so that service employees often fail to apply the caps and thus nullify the effect of the waterproof cover.

The device of the present invention overcomes all of the above difficulties, materially simplifies the construction, reduces the cost tremendously and provides a cover plate or lid which is always closed when the plug is removed from the outlet. The hinge is self-contained, i.e. molded integral with the cover encloses the springs to protect them, improves the appearance of the completed unit and forms an effective seal under all conditions.

For a better understanding of the invention reference should now be had to the drawings showing the cover or lid 10 applied to a conventional wall or face plate 12, either of the metal type or one which is molded from one of the better grade plastics having a smooth exterior surface. Such a plate is conventionally of rectangular configuration and sized to completely cover the opening at the face of the switch or wall box to which it is attached by screws such as indicated at 13 and 14 which take into threaded apertures in lips inturned from the ends of the wall box.

Not shown in the drawings is the wall box and suitable known gasketing material arranged between its forward edges and the undersurface of the wall plate or between the downturned edges of the wall plate and the surface of a wall or the like in which the box is embedded. This insures a Waterproof connection at these junctions, without which the waterproof cover would be a futile addition.

As seen in FIGURES 2 and 3 the wall plate 12 is apertured at 15 to expose the face 16 of a known convenience outlet having slots 17 in a customary manner for accept- .ing the blades of an attachment plug, all as heretofore used for many years. Normally the face of the outlet 16 is substantially flush with the front face of the plate. Since the plate is usually sealed to the edges of the box it remains only to seal the outlet opening 15 and the slots 17 against the entrance of moisture and this is done by means of the cover plate or lid 10 which is molded of a plastic of resilient characteristics to a relatively thick section having an outwardly turned pointed lower tip 18 to facilitate lifting for access to the outlet.

The lid, and its integral hinge portion about to be described, is preferably formed from a plastic such as that known as polypropylene because of its unique hinge characteristics.

Flexible plastics such as vinyls and low density polyethylenes have been used previously for flexing in hingetype components, but in polypropylene there exists a rigid yet resilient material which, in thin sections provides virtually unlimited flex life and, consequently, relatively rigid components such as containers or lids can be molded with integral hinges. Such hinges act in a way which is not fully understood, but probably results from the characteristics of polypropylene including its crystalline nature which permits substantial increases in strength through orientation or stretching; its high elongation beyond the yield point; its complete resistance to stress cracking; and the fact that it forms a tough skin during molding or extruding. As molded, a polypropylene hinge web has unit tensile strength and thickness equivalent to that of any other section of the molding. It therefore has some resistance to flexing. However, on the first flex of the relatively confined hinge area, fiber stress in the outer surface causes elongation exceeding the yield point, thus orienting the crystallite structure and causing necking down in that area. Such orientation increases tensile strength. Further flexing will increase orientation and the hinge will actually become stronger with use and it has been reported that polypropylene hinges have been flexed from 300,000 to over a million flexes throughout a 180 angle at temperatures between 75 and minus 20 F. with no indication of failure.

The first purpose, of course, of the cover is to seal around the outline of the opening and this is achieved by molding integral with the heavy portion 10 of the lid' or cover a rim along the irregular outline best seen in FIGURE 2. This rim is an inwardly projecting rib 21 of substantial thickness in a direction at right angles to its height, and supports an integral extension in the form of a thin lip 22, best seen in FIGURE 4, which is given a decided outward flare to an angle of approximately 45 so that when engaging the surface of the plate as seen in FIGURE 3 it tends to bend outwardly, so that any irregularities which sustain the first load are pressed out of the flexible material and complete sealing is achieved under the pressure of the springs about to be described.

As best seen in FIGURE 4, above, the heavy section forming the lid 10 the integral moulded structure is reduced in thickness beyond the upper or horizontal line 20 of the gasket, but with the outer surface 24 continuous with the outer surface of 10. The inner surface is, however, brought closer to the outer surface providing the section 25 of uniform thinness and width, which at spaced points 26 and 27 is necked in by means of opposed transverse grooves forming two parallel hinge lines spaced apart just slightly more than the diameter of the springs which are used to maintain the lid closed and which are housed between the portion 25 immediately attached to the thick lid section and the upper portion 29 which is turned back under the section 25 when the two hinges are bent each through an angle of 90 as shown in FIGURE 3, leaving the intermediate section 28 extending normal or substantially so to the plane of the cover plate. Each of the springs 30 is a multi-coil close helix having an arm 31 extending from its outer end, bent slightly at 32 to extend substantially parallel to the outer face of the lid 10 and then having an inturned short end 33 received in an appropriate notch 34 in the upper face of the lid. The opposite spring is reversely formed. The other or inner end of each spring is turned downwardly, as seen at 35 in FIGURE 3, and then extended parallel to the face of the wall plate and formed into an eye 37 which fits beneath the head 38 of a rivet 39 which passes through an appropriate hole 40 in the part 29 of the hinge section and the corresponding opening 41 in the cover plate and is headed over beneath. Note that this does not have to be a waterproof joint since it is outside of the area sealed by the lip 22.

Naturally each of the springs is bent to a position considerably beyond that indicated in FIGURES 1 and 3 so that the arm 32 must be flexed outwardly to be hooked over the lid whereby to hold it with considerable pressure in a closed position.

The notch 40 seen in FIGURE 2 in the portion 29 between the rivets therein exposes the area through which the mounting screw 13 for supporting the wall plate passes. This screw can easily be inserted when the lid is held in the raised position.

There is, thus, provided a one-piece lid, gasket, hinge and mounting section serving to waterproof the outlet which extends through the aperture 15 in the wall plate. The lid is easily lifted by inserting a finger beneath the outwardly curved lower end 18 thereof and it must be lifted somewhat beyond the position shown in dotted lines in FIGURE 3 to permit the insertion of the usual attachment plug. The lid merely rests against the cord or top of the attachment plug while the latter remains inserted but as soon as the plug is withdrawn the lid im- 4 mediately closes and seals to keep out water, moisture and dirt to say nothing of insects, pollen and other outdoor pests.

I claim: 1. For use .with the rigid, cover plate perforated for exposing the face of an electric convenience outlet, a

one-piece lid and hinge structure moulded of a bendable plastic into a thick lid portion, an integral, thin, flexible gasket portion protruding from the under surface of the lid portion to enclose an area larger than the plate perforation exposing the outlet, a thin integral extension from one end of said lid portion, said extension being transversely necked-in at two spaced positions to form parallel hinge lines to elevate the lid portion from the cover plate, a coil closure spring, said extension having a perforation above the last hinge line, said spring having a looped end, a fastener means extending through said loop, said perforation, and a cover plate to hold them assembled together, and an arm on said spring extending to engage the front of the lid to urge it toward the cover late.

p 2. The structure as claimed in claim 1 in which the one-piece lid and hinge structure are moulded from polypropylene.

3. The combination with a rigid wall or cover plate having an opening for exposing the face of a convenience outlet, of a combined cover and hinge unit including a one-piece moulded plastic structure having a relatively thick, substantially rigid lid portion larger than said opening, a sealing lip integral with and extending from one face of said lid portion adapted to surround and enclose an area larger than said opening, an integral extension from one edge of said lid of substantially reduced thickness, two parallel lines of narrow necked-in areas spaced apart and beyond said edge to form hinges whereby the remote portion of the extension may be doubled under the immediate portion, means securing said remote portion to the face of said wall plate above said opening and spring means supported by said securing means arranged to bias said lid toward and said lip closely against the face of the plate to seal said opening against moisture.

4. The structure as claimed in claim 3 in which the cover and hinge unit is moulded from polypropylene.

5. A wall plate of rigid material for and having an opening for exposing the face of a convenience outlet, a lid for closing said opening formed of a thick moulded section of polypropylene larger than said opening, but smaller than said plate, a flexible lip gasket integral with and extending from the back face of said lid and enclosing an area substantially centered in and larger than said opening, a thin integral extension from the upper edge of said lid, spaced parallel necked-in grooves across the full width of said extension forming hinges each bent in the same direction to an angle of a pair of helical springs housed between the overlying portions of said extension, a rivet securing the inner end of each spring to said plate and passing through the outermost part of said extension to secure it to said plate, and each spring having an arm projecting from its outer end alongside said lid portion, and an end on each arm turned inwardly at an angle of 90 and overlying said lid to press the lid gasket against said plate.

References Cited in the file of this patent 'UNITED STATES PATENTS 2,852,054 Motley Sept. 16, 1958 2,867,345 Bellek Jan. 6, 1959 2,997,520 Kinsman Aug. 22, 1961 

1. FOR USE WITH THE RIGID, COVE PLATE PERFORATED FOR EXPOSING THE FACE OF AN ELECTRIC CONVENIENCE OUTLET, A ONE-PIECE LID AND HINGE STRUCTURE MOULDED OF A BENDABLE PLASTIC INTO A THICK LID PORTION, AN INTEGRAL, THIN FLEXIBLE GASKET PORTION PROTRUDING FROM THE UNDER SURFACE OF THE LID PORTION TO ENCLOSE AN AREA LARGER THAN THE PLATE PERFORATION EXPOSING THE OUTLET, A THIN INTEGRAL EXTENSION FROM ONE END OF SAID LID PORTION, SAID EXTENSION BEING TRANSVERSELY NECKED-IN AT TWO SPACED POSITIONS TO FORM PARALLEL HINGE LINES TO ELEVATE THE LID PORTION FROM THE COVER PLATE, A COIL CLOSURE SPRING, SAID EXTENSION HAVING A PERFORATION ABOVE THE LAST HINGE LINE, SAID SPRING HAVING A LOOPED END, A FASTENER MEANS EXTENDING THROUGH SAID LOOP, SAID PERFORATION, AND A COVER PLATE TO HOLD THEM ASSEMBLED TOGETHER, AND AN ARM ON SAID SPRING EXTENDING TO ENGAGE THE FRONT OF THE LID TO URGE IT TOWARD THE COVER PLATE. 